Management of women with PCOS using myo-inositol and folic acid. New clinical data and review of the literature

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1 DE GRUYTER Hormone Molecular Biology and Clinical Investigation. 2018; Original Article Pedro-Antonio Regidor 1 / Adolf Eduard Schindler 2 / Bernd Lesoine 3 / Rene Druckman 4 Management of women with PCOS using myo-inositol and folic acid. New clinical data and review of the literature 1 Exeltis West Europe, Adalperostr. 84, Ismaning, Germany, Phone: , Fax: , pedro-antonio.regidor@exeltis.com 2 Institut für medizinische Forschung Essen, Essen, Germany 3 Centre for Reproductive Medicine Bogenhausen, Munich, Munich, Germany 4 ANEMO, Nice, France Abstract: Introduction: The use of mg myo-inositol μg folic acid per day is a safe and promising tool in the effective improvement of symptoms and infertility for patients with polycystic ovary syndrome (PCOS). In addition, PCOS is one of the pathological factors involved in the failure of in vitro fertilization (IVF). Typically, PCOS patients suffer of poor quality oocytes. Patients and methods: In an open, prospective, non-blinded, non-comparative observational study, 3602 infertile women used myo-inositol and folic acid between 2 and 3 months in a dosage of mg myo-inositol μg folic acid per day. In a subgroup of 32 patients, hormonal values for testosterone, free testosterone and progesterone were analyzed before and after 12 weeks of treatment. The mean time of use was 10.2 weeks. In the second part of this trial it was investigated if the combination of myo-inositol + folic acid was able to improve the oocyte quality, the ratio between follicles and retrieved oocytes, the fertilization rate and the embryo quality in PCOS patients undergoing IVF treatments. Twenty-nine patients with PCOS, underwent IVF protocols for infertility treatment and were randomized prospectively into two groups. Group A (placebo) with 15 patients and group B (4000 mg myo-inositol +400 μg folic acid per day) with 14 patients were evaluated. The patients of group B used 2 months myo-inositol + folic acid before starting the IVF protocol. For statistically analyses Student s t-test was performed. Results: Seventy percent of the women had a restored ovulation, and 545 pregnancies were observed. This means a pregnancy rate of 15.1% of all the myo-inositol and folic acid users. In 19 cases a concomitant medication with clomiphene or dexamethasone was used. One twin pregnancy was documented. Testosterone levels changed from 96.6 ng/ml to 43.3 ng/ml and progesterone from 2.1 ng/ml to 12.3 ng/ml in the mean after 12 weeks of treatment (p < 0.05) Student s t-test. No relevant side effects were present among the patients. The women in the IVF treatment the group A showed a higher number of retrieved oocytes than group B. Nevertheless, the ratio follicle/retrieved oocyte was clearly better in the myo-inositol group (= group B). Out of the 233 oocytes collected in the myo-inositol group, 136 where fertilized whereas only 128 out of 300 oocytes were fertilized in the placebo group. With regards to the oocytes quality, better data were obtained in the myoinositol group. More metaphase II and I oocytes were retrieved in relation to the total number of oocytes, when compared with the placebo group. Also, more embryos of grade I quality were observed in the myo-inositol group than in the placebo group. The duration of stimulation was 9.7 days (±3.3) in the myo-inositol group and 11.2 (±1.8) days in the placebo group and the number of used follicle-stimulating hormone (FSH) units was lower in the myo-inositol group in comparison to the placebo group: 1850 FSH units (mean) versus 1850 units (mean). Discussion: Myo-inositol has proven to be a new treatment option for patients with PCOS and infertility. The achieved pregnancy rates are at least in an equivalent or even superior range than those reported using metformin as an insulin sensitizer. No moderate to severe side effects were observed when myo-inositol was used at a dosage of 4000 mg per day. In addition, our evidence suggests that a myo-inositol therapy in women with PCOS results in better fertilization rates and a clear trend to a better embryo quality. As by the same way the number of retrieved oocytes was smaller in the myo-inositol group, the risk of a hyperstimulation syndrome in these patients can be reduced. Therefore, myo-inositol also represents an improvement in IVF protocols for patients with PCOS. Keywords: infertility, metabolic changes, myo-inositol, PCOS Pedro-Antonio Regidor is the corresponding author Walter de Gruyter GmbH, Berlin/Boston. 1

2 Regidor et al. DE GRUYTER DOI: /hmbci Received: October 9, 2017; Accepted: January 15, 2018 Introduction The polycystic ovary syndrome (PCOS) is a disease that causes irregular bleedings, chronic anovulation androgen excess and a typical ovarian ultrasound feature [1]. It is the most common cause of infertility affecting between 5% and 10% of women during their reproductive age [2]. The PCOS etiopathology is not clear, but most probably a strong genetic cause, influenced by gestational environment and lifestyle, seems to be the key factor. The European Society of Human Reproduction and Embryology and the American Society for Reproductive Medicine defined, at a meeting in Rotterdam 2003, the criteria for the definition of this disease [3], [4]. To reach a general agreement on diagnostic criteria many investigations have focused, independently of the above-mentioned disorders on the impaired glucose tolerance, which affects 30 40% of women with PCOS [5] and on insulin resistance. Hyperinsulinemia due to insulin resistance occurs in up to 80% of women with PCOS and central obesity as well as in 30 40% of lean women diagnosed with this syndrome [6], [7], [8]. The related hyperinsulinemia could induce an excess of androgens production in PCOS women through two different ways: the first is direct stimulation of ovaries to produce androgens, and the second is the reduction of sex hormone binding globulin (SHBG) serum levels [9]. Due to the key role of insulin in the syndrome etiopathology, for many years insulin sensitizers such as metformin, pioglitazone or troglitazone have been considered as possible therapeutic options. Metformin has been widely used on patients with a hyperinsulinemic status for the improvement of ovarian dysfunction with consecutive anovulation, irregular menstrual cycles and infertility problems [6], [10]. Nevertheless metformin, when used in the therapeutically dose range, has shown to have several side effects such as flatulence, diarrhea and nausea, so that many patients are unable to use this treatment option in gynecology for a long period of time [11], [12]. In addition, to the common use of metformin and other insulin sensitizer agents for the treatment of PCOS, in recent years other therapeutic alternatives have been investigated, especially myo-inositol. The substance inositol is a chemical compound with the formula C 6 H 12 O 6 or (-CHOH-) 6, a six-fold alcohol (polyol) of cyclohexane with five equatorial and one axial hydroxyl group. It is widely found in nature. Nine different stereoisomer forms have been described, but myo-inositol is the most common found in nature. In fact, myo-inositol is very often found in many plants and in the tissues of animals. The second most common form is D-chiro-inositol. It is important to distinguish between the lecithin formulation that is bioavailable for humans and the phytate formulation of corns that are not bioavailable. Food with the highest concentration of myo-inositol are fruits, beans, corns and nuts [13]. Inositol was defined in the past as myometrial sugar, however, it is not a substance belonging to the carbohydrate group. Defining inositol as a vitamin B is also being controversially discussed as inositol is not an essential substance and it can be produced in human cells from glucose [14]. In fact, several studies have proved that the inositol molecule is directly involved in the insulin cellular signaling. Regarding PCOS, several studies have shown that one of the mechanism of insulin deficiency results from in the inositolphosphoglycan (IPG) mediator and that a deficiency of inositol in the IPGs is responsible for insulin resistance. It has been demonstrated that the administration of D-chiro-inositol (intracellularly converted from myo-inositol) reduces insulin resistance [15], [16] (see Figure 1). Figure 1: Mechanism of action of myo-inositol in the cell. Studies have suggested that an impairment of the insulin pathway could be due to a defect in the IPGs second messenger [17], [18]. IPGs play a role in activating enzymes that control glucose metabolism [19], [20]. In PCOS 2

3 DE GRUYTER Regidor et al. women, a defect in tissue availability or altered metabolism of inositol or IPGs mediators may contribute to insulin resistance [21]. Previous studies have demonstrated that myo-inositol is able to restore spontaneous ovarian activity in PCOS women and consequently fertility in many of these cases [22]. Nevertheless many of these PCOS women require techniques of assisted reproduction to achieve a pregnancy. However, more than 60% of in vitro fertilization (IVF) cycles do not result in a pregnancy and poor oocyte quality is the main cause of fertilization failure [23]. Therefore, assisted reproductive techniques nowadays focus on obtaining high quality oocytes rather than high numbers of oocytes and embryos [24]. In IVF techniques, the supplementation with myo-inositol is positively correlated to a meiotic progression of mouse germinal vesicle oocytes, enhancing intracellular Ca 2+ oscillations [25]. In follicular human fluids, higher concentrations of myo-inositol represent a marker of good quality oocytes [26]. If myo-inositol or D-chiro-inositol have a better effect on the quality of oocytes in IVF cycles must be elucidated. The paradox theory published and discussed by Nestler and Carlomagno [27], [28] suggested that D-chiro-inositol, in not physiological high dosages, had a negative impact on the quality of oocytes of PCOS women, as the ovarian epimerase function is not altered in PCOS patients so that the myo-inositol levels in the follicular fluids remain low if only D-chiro-inositol is supplemented. The Consensus Conference on Myoinositol and D-chiro-Inositol postulated that the future ideal inositol supplementation should therefore contain a ratio of 40:1 between myo-inositol and D-chiro-inositol [29]. The approach of myo-inositol with 3 mg melatonin is also a possible way to improve oocyte quality. Rizzo et al. [30] and Unfer et al. [31] were able to obtain oocytes with a better quality when the PCOS women were treated with a combination of myo-inositol 4 g μg folic acid +3 mg melatonin per day in comparison to formulations without melatonin. Studies also report a very good safety profile of the molecule, even when administered up to 12 g/day, where only mild gastrointestinal side effects have been reported [32]. For the first time in Germany myo-inositol has been now evaluated with regard to its efficacy in women with a PCOS and infertility. In the first part of this investigation observational data were evaluated to determine the pregnancy rates under the use of this combination in patients with a PCOS, to establish if this molecule can be used as a safer treatment option for the fertility improvement of this disease. In the second part of the investigation it was investigated if pretreatment with myo-inositol and folic acid as a food supplement could improve the oocyte quality, the ratio between follicles and retrieved oocytes, the fertilization rate and the embryo quality in PCOS patients undergoing IVF treatments. Due to the paradox theory, D-chiro-inositol was not used and melatonin 3 mg/day was excluded because of its drug status in Germany. Patients and methods A standardized questionnaire was developed (Figure 2) and presented to 245 gynecologists in Germany, between June 2015 and March During this time reports were generated of 3602 women with a PCOS and infertility according to the Rotterdam classification. The women started with the intake of myo-inositol and folic acid at a dosage of mg myo-inositol and μg folic acid per day and used it for at least 2 3 months. The primary outcome of the study was to determine the ovulatory function restoration and the pregnancy rate after treatment. The pregnancies were documented by the gynecologists and registered in a database, and these women were followed during the whole pregnancy. Secondary outcome was the evaluation of side effects reported in those patients undergoing treatment. In a subgroup of patients, hormonal values were also evaluated. The values investigated were testosterone, free testosterone and progesterone. In these group of patients, the pregnancies outcome has also been checked. 3

4 Regidor et al. DE GRUYTER Figure 2: German questionnaire. Twenty-nine patients with PCOS, underwent IVF protocols for infertility treatment in the Centre for Reproductive Medicine Bogenhausen in Munich, Germany and were randomized prospectively into two groups. Group A (placebo) with 15 patients and group B (4000 mg myo-inositol +400 μg folic acid per day) with 14 patients were evaluated. The patients of group B used for 2 months a combination of myo-inositol and folic acid before starting the IVF protocol. The patients aged <40 years with PCOS indicated by oligomenorrhea and/or hyperandrogenism and/or hyperandrogenemia and/or typical features of ovaries on ultrasound scan were enrolled in this study. At least two of the abovementioned criteria were present in all the patients. The women had no other medical conditions causing ovulatory disorders such as hyperprolactinemia or thyroidal disorders or Cushing syndrome. Controlled ovarian hyperstimulation In all patients, the stimulation was started on cycle day 2 or 3 with a single dose of 150, i.e. gonadotropin β. From the 6th stimulation day all patients received the antagonist Ganirelix to prevent a premature ovulation. Ovulation induction was performed on all the patients on day 10th or 11th of the stimulation either with 5000iE hcg, or in case of risk of an over hyperstimulation syndrome with 0.2 mg DecapeptylGnRH-agonist. Follicular puncture was performed on all patients exactly 35 h after induction of ovulation. Those patients at risk of an over stimulation syndrome did not receive an embryo transfer but the fertilized oocytes were cryconservated at the pre-embryonic stage. Embryo transfer (maximum two embryos) was performed after 2, 3 or 5 days. Pregnancy tests were performed always 14 days after follicular puncture. Luteal phase Vaginal administration of 400 mg micronized progesterone was started on the day of ovum pick-up and treatment was continued until either a serum pregnancy test result was negative or an embryonic heart was sonographically confirmed. Data were obtained concerning the number of follicles, the number of retrieved oocytes, ratio follicles/oocytes, quality of oocytes, fertilization rates and embryo quality. For statistically analyses Student s t-test was performed to compare the effects between the treatment groups. 4

5 DE GRUYTER Regidor et al. Results The data of 3602 patients with PCOS were evaluated. According to the obtained records 2520 women experienced an improvement of their menstrual cyclicity towards ovulatory cycles. Among them, a total number of 545 women became pregnant. The pregnancies occurred after the intake of 2 3 months of myo-inositol and folic acid. This means a ratio of 15.1% of the investigated women become pregnant during this observational study. No twin pregnancies were documented. No relevant side effects have been reported in the patients taking myo-inositol and folic acid product. Figure 3 depicts the data. In the subgroup of 32 patients where hormonal values were evaluated a significant improvement of androgen levels were observed and a rise in the progesterone values. Figure 3: Number of patients and pregnancy rates. This is shown in Table 1. Figure 2 depicts the used German questionnaire. Furthermore, out of these 32 women who became pregnant, five of them experienced an miscarriage, whereas the remaining 27 delivered healthy newborns. Table 1: Hormonal data before and after treatment with myo-inositol. Total testosterone, ng/dl Free testosterone, ng/dl Progestrone, ng/dl Before treatment 96.6 ± ± ± 0.6 After treatment 43.3 ± ± ± 1.3 During the IVF treatment the group A (= placebo group) showed a higher number of retrieved oocytes than group B. Nevertheless, the ratio follicle/retrieved oocyte was clearly lower in the myo-inositol group (= group B) (p < 0.05) (see Figure 4). Figure 4: Ratio of follicles and retrieved oocytes. Statistically differences (p < 0.05) were observed. The number of developed follicles was lower in the myo-inositol group and in relation to this a higher number of oocytes were retrieved. 5

6 Regidor et al. DE GRUYTER From the obtained 233 oocytes in the myo-inositol group 136 were fertilized whereas only 128 of 300 oocytes were fertilized in the placebo group (p < 0.05) (see Figure 5). Figure 5: Relation between the myo-inositol treatment and the fertilization rate in both groups. Higher rates (p < 0.05) were observed in the myo-inositol group in comparison to the placebo group. In relation to the quality of the oocytes, better data were obtained in the myo-inositol group. More metaphase II and I oocytes were retrieved in relation to the total number of oocytes when compared with the placebo group (p > 0.05) (see Figure 6). Figure 6: Oocyte quality and treatment with myo-inositol or placebo (p = 0.06). The last analysis that was performed on the quality of embryos. More embryos of grade I quality were observed in the myo-inositol group than in the placebo group (p < 0.05) (Figure 7). This difference was, as the analyses done for the fertilization rate and the ratio follicles retrieved oocytes, statistically significant. Figure 7: Embryo quality after treatment with myo-inositol or placebo. Higher number of embryos with grade I were observed in the myo-inositol group (p < 0.05). The amount of follicle-stimulating hormone (FSH) units used as lower in the group of women the received myo-inositol. A mean of 1750 unit were used (minimum 1350 units and maximum 2250 units) whereas the 6

7 DE GRUYTER Regidor et al. used amount in the placebo group was higher. Mean used units: 1850 with a minimum 1500 and a maximum of 2300 units (p > 0.05). Regarding the amount of stimulation days, a significant difference was observed. The myo-inositol patients were stimulated with FSH in the mean 9.7 days (±3.3 days) and the placebo group 11.2 days (±1.8 days). This difference was significant (p < 0.05). Discussion PCOS is one of the most common endocrine disorders affecting women. Insulin resistance and hyperinsulinemia are often found in a high proportion of women with PCOS. A defect in insulin action has been postulated, possibly because of a deficiency of D-chiro-inositol, which is a component of inositol phosphoglycans. Insulin-lowering medications, particularly myo-inositol, represent novel therapies for restoring spontaneous ovulation, with a potential positive effect also on human oocyte meiotic maturation. This therapy appears to influence steroidogenesis directly, reducing the androgen production in theca cells. It was shown that inositol administration increases the action of insulin in patients with PCOS, thereby improving ovulatory function and decreasing serum testosterone concentration [21], [33], [34], [35], [36]. Despite clear limitations of observational studies, the presented data are reliable, as a wide range of patients was analyzed. This study could show that a new treatment option for patients with a PCOS and infertility is available. Seventy percent of the patients had restored ovulation after the treatment. Furthermore, the achieved pregnancy rates are at least in an equivalent or even superior range than those reported using the insulin sensitizer metformin. Karimzadeh and Javedani [37] described a pregnancy rate of 14.4% in a cohort of 90 women and Legro et al. [38] of 12.3% in a cohort of 75 women with PCOS. Another important evidence is also related to the difference of myo-inositol and metformin in terms of the safety profile and compliance for patients. In patients taking metformin, side effects have been commonly reported, from mild up to severe gastrointestinal side effects, such as abdominal pain, nausea, diarrhea. Only in rare cases very severe side effects as lactic acidosis have been found. On the other hand, myo-inositol seems to be a safe and well-tolerated approach, which is able to obtain similar results as those described with metformin. Many studies have demonstrated in the in recent times that an improvement in the rates of ovulation and regularization of menstrual cycles was obtained by the combined use of 4 g myo-inositol with 400 μg folic acid per day. Gerli et al. [39] could show, in a prospective study, that the group of patients receiving myoinositol + folic acid experienced in 82% of the cases an ovulation, whereas this was only observed in 63% of the cases in the group of patients who received a placebo. In the same way, 70% of the patients of the myo-inositol group developed regular menstrual cycles after 16 weeks of treatment, whereas only 13% of the women did so in the placebo group. In a study of Raffone et al. [40], where a comparison between the administration of myo-inositol ( g μg per day) and metformin (1500 mg per day) in women with a PCOS was performed, it could be shown that the number of pregnancies was clearly higher in the myo-inositol group than in the metformin group of patients. Some other studies have shown the efficacy of myo-inositol in the improvement of the fertility of PCOS patients due to its improvement of the insulin resistance in these women [41], [42], [43]. With regard to the outcome of IVF cycles in women with a history of a PCOS Papaleo et al. [33] could show that in patients with PCOS the treatment with myo-inositol and folic acid, but not folic acid alone, reduced germinal vesicles and degenerated oocytes at ovum pick-up without compromising total number of retrieved oocytes. In the same way, the amount of stimulation days was, as in our study, shorter in the myo-inositol treated women showing a faster response of the ovarian follicles to FSH stimulation due to the myo-inositol effects. On the other hand, PCOS women have an increased risk of hyper stimulation syndrome [44]. High levels of serum ovarian androgens are associated with the production of elevated serum E2 levels after gonadotropin ovarian stimulation. The study of Papaleo et al. [45] showed that PCOS patients treated with myo-inositol and gonadotropin had a significant reduction in E2 levels after human chorionic gonadotropin (hcg) administration. This was also related to the lower number of IVF cycles canceled because of high E2 levels (sign of hyper stimulation syndrome). In addition to this, myo-inositol is an important constituent of follicular fluid, playing a key role in both nuclear and cytoplasmic oocyte development. In fact, supplementation with myo-inositol in the IVF technique is positively associated to meiotic progression of mouse germinal vesicle oocytes, enhancing intracellular Ca2 oscillation [44]. In human follicular fluids, higher concentrations of MI provide a marker of good-quality oocytes [31], [36], [45]. Beside the increased ratio follicles/retrieved oocytes and the higher fertilization rate in the group of women that used myo-inositol, a more important result was the increased number of top-quality (score 1 vs. 2) embryos 7

8 Regidor et al. DE GRUYTER in the myo-inositol group. These data suggest that, besides increasing the fertilization rate, myo-inositol supplementation has also an effect on the overall quality of the oocyte pool. Many studies have been performed that show that the treatment with myo-inositol + folic acid in the classical dosage ( g myo-inositol +200 μg folic acid per day) leads to significant positive changes of metabolic and hormonal parameters. Constantino et al. [46] could show in a double-blinded, placebo-controlled study that myo-inositol lead to a statistically significant improvement of the blood pressure, triglycerides, cholesterol, glucose and insulin values after a 75 mg oral glucose tolerance test. These improvements were achieved after a treatment period of 16 weeks. The evaluated hormonal values showed a significant decrease of the total and free testosterone serum levels and at the same time the progesterone levels, as a marker of ovulation, experienced a significant rise in the group that received myo-inositol (see Table 1). This could show that myo-inositol did not only lead to positive changes in metabolic parameters but also to a reduction of elevated androgenic values and subsequently to an improvement of skin problems such as acne or hirsutism. These data can be supported by our own data as a rise of progesterone from a value of 2.1 ng/ml to a value of 12.3 ng/ml could be observed. At the same time a reduction in the levels of testosterone (from 96.6 ng/ml to 43.3 ng/dl) and free testosterone (from 1.2 ng/ml to 0.35 ng/ml) could also be observed. This confirms that myo-inositol is not only an effective alternative in the treatment of PCOS patients but also a secure one as no side effects could be observed in the standard dosage. This is relevant as the compliance of the use rises resulting in better outcomes in the management of ovulation, hyperandrogenism and metabolic parameters on patients with a PCOS. Additional investigations on larger number of patients are needed to further characterize the impact of myoinositol treatment on oocyte follicular development and oocyte maturation, and its implication in the stimulation and pregnancy outcomes in IVF procedures. Author Statement Research funding: The authors report no funding. Conflict of interest: Pedro-Antonio Regidor is Medical Director for Western European and Germany of Exeltis, a member of the INSUD Group, which distributes myo-inositol in Germany. Bernd Lesoine, Adolf Eduard Schindler and Rene Druckman declare no conflict of interest. Informed consent: Informed consent was obtained from all participants. 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